It is now recognised that so-called glass-ionomer and polycarboxylate cements may be potentially the most efficient and suitable substances yet developed for dental cementation.
Glass-ionomer cements generally comprise a mixture of an ion-leachable glass in particulate form together with a cross-linkable poly(carboxylic acid). When a solvent is added to the cement, multivalent ions become leached from the glass and cross-link the poly(carboxylic acid) during curing. It has been shown that such glass ionomer cements exhibit a degree of adhesion to enamel, dentine and specially surface treated platinum and gold alloys. However, it has been reported that the glass-ionomer cements do not bond to any significant degree to porcelain and are thus precluded from use in dental restorative systems utilising ceramic materials. This work is discussed in Hotz et al., British Dental Journal 142:2 41-47 (January) 1977. Such glass ionomer cements are commercially available under the trade marks ASPA and FUJI ionomer.
Polycarboxylate cements similarly involve the cross-linking of a poly(carboxylic acid) by means of multivalent ions. However, in this case the poly(carboxylic acid) is mixed with zinc oxide particles, which normally include a minor proportion of magnesium oxide. Commercially available polycarboxylate cements include Durelon (available from ESPE) and PCA (available from S. S. White).